D-shell hole punches?

On Tue, 11 Mar 2008 15:24:53 -0400 (EDT), der Mouse wrote: [...] I've gone a bit of different route than the use of punches and nibblers - the former being too expensive for an occasional job and the latter too much of a pain. I use a spiral cutter and a template. I picked up a cheap spiral cutter from my neighborhood China Town store and modified it by adding a template follower to the head. I generate the template on a cad program, expand it twice needed and print onto card stock which I then hand cut. I use this template to cut the final template in plastic. Drill a hole at the cut-out site, clamp the template on the target piece and cut away. You should ensure that you get a metal cutter if you are doing steel or aluminum (aluminium). I found that taking two steps to generate the template results in a much better result. My cutter was bought on sale for under US$ 20 for a one-off job and kept around and modified when I ran into a situation that needed a odd shape cut-out. A good cutter will run under US$ 75 and the bits are on the order of 5-10. I've used it to do D-holes for BNCs and power cords, connectors, as well as many other openings such as for fans. CRC